Steadily rising temperatures have been prompting birds to begin their migration patterns either too early or too late.

Global warming tends to stir up a lot of debate not only among the scientific community but among everyone else as well. Whether or not the entire environment is actually becoming warmer is a subject I feel comfortable leaving to environmental scientists, but we can’t deny that Earth’s climate is experiencing change. The changes in climate that we are constantly experiencing lead to changes in the migration patterns of birds.

Our Warming Climate

The average surface temperature of the earth has been steadily warming over the past century but the most accelerated warming has occurred within the last couple of decades. Some studies indicate that the actual surface temperature is 0.74 degrees Celsius higher than it was a century ago. While this may not seem like that big of deal, it can actually be detrimental to bird populations and every other aspect of the ecosystems that they have a correlation with.

Warmer temperatures are causing birds to begin their migration patterns earlier than usual. They are also causing birds to alter the amount of time in which they complete their migrations. Numerous studies have been done to determine the extent to which bird migration patterns are being affected by climate change and although variations across species and geographic regions exist, it can be stated that bird migration patterns are affected negatively.

Birds take cues from their bodies as well as the environment to know when to start migrating. Most species appear to time their arrival on breeding grounds based on climate or other environmentally related factors. Hummingbirds, for example, are believed to be stimulated to migrate by changes in sunlight and temperature. If temperatures warm up earlier in the year, hummingbirds might be prompted to migrate too early and then not be able to survive the climates that they migrate through.

Speed of Migration

Because different species of birds migrate at different speeds, tracking exactly how climate change affects their migration patterns is nearly impossible unless you look at each species or even subspecies individually. Scientists across the globe are making efforts to do so but a common theme can be derived from their efforts. The speed at which at particular bird migrates influences the likelihood of their survival along their migration routes.

Birds that take their time along their migration routes are better able to assess their surrounding and if the temperature is warm enough for them to move on. This is advantageous because birds that arrive too early at their destination face the possibility of adverse conditions and limited resources. This also gives slow moving birds a chance to adapt to temperature change without risking temperature shock. Species that move too quickly along their migration route may be less able to adapt to temperature change thereby putting them at risk. Arriving at a site too late is just as much of a disadvantage as arriving too early because breeding territories and high quality mates may have already been claimed by other birds.

Migration Relationships

Interestingly enough, butterflies are also affected by climate change but according to various studies, they are able to adapt much quicker to the changes because of their shorter life cycles. This is problematic because if birds are unable to keep up with butterflies, the relationship between birds and butterflies will be greatly altered and birds will lose out of a major food resource during their migrations.

Hummingbird migration patterns are extremely difficult to track because of the solidarity of humming birds but they are prime examples of how specific environmental conditions are necessary in order to complete a migration route successfully. Because of their size, hummingbirds are extremely sensitive to temperatures so venturing into a climate that is just a couple of degrees to cold can be detrimental for the hummingbird.

They also need to be able to keep up with food resources because their metabolism requires them to eat and drink constantly. As climate change ensues, hummingbirds and other avian species may not be able to adjust their migration patterns quickly enough to survive as a species.

Understanding how climate change alters migration responses in birds is critical for being able to predict the species most at risk when it comes to future climate change. When species are put at risk, it not only affects that particular species, but it affects every other aspect of the ecosystem in which that species is involved in.

It is in our best interest, as well the best interest of our climate, to understand how climate change affects various species. If we know and understand the relationship, we can better focus conservation efforts.

Ernie Allison is a nature writer with a particular interest in birds. He is dedicated to using his writing skills to bring awareness to conservation issues concerning birds. To help further this mission, he writes for the hummingbird migration expert, birdfeeders.com